It was found that most users / customers did not have any use for the full data report so that practice stopped in order to save processing time / cost. However, some people would still like the full report so it is available as a paid service and ordering option.
Sorry, but this "trust us" argument just doesn't cut it. After nagging support i got the cal reports for my DMM7510 and DAQ6510 respectively. Keysight gives you the factory cal report in an enclosed letter, no fuss. Who, in their right mind, would
not want to have the "starting point", e.g. the initial factory calibration, of a meter with 6.5 digits or better resolution? Are customers using it as a interior decoration because of the nice colour screen, or somesuch? Most probable it's marketing dept BS made up to create the illusion of meeting customer expectations, while the real motive is increasing profit (saving a few minutes in mfg, getting some sheepish customers to pay extra for a report they should have received upfront). This is exactly like the statement "everybody has battery anxiety with electric cars, so we will only supply the cars on a lease basis. No one wants to outright buy the cars, including the 'risky' batteries, so we don't offer that option" - yeah, sure.
OTOH, I think you are doing the LM399 in the meter a disservice - my experience from a KS 34465A and a DAQ6510 is that, yes, the meters drift a little initially but the references are definitely pre-burned-in or selected for lowest drift, which is one of the things you
do pay for with premium brand meters. I have another meter from a chinese mfg, SDM3065X, that very obviously had the LM399 just soldered in without any selection or pre-aging done; measurement was spot on day 1, not so much after a month (drifted out of 1y spec, even.)
I'm a bit sensitive to word weaseling, as you may have guessed, and I am quite specifically allergic to "the customers wanted this, so we listened to them" inverted argument, when the end result is bad for the customer and more $$$ for the mfg.